Petbe be villiers



' ,UNITED STATES PATENT Orrlenn PETER DE VILLIERS, OF ST. LEONARDS-ON-SEA, ENGLAND.

INOXIDIZABLE ALLOY.

SPECIFICATION forming part of Letters Patent No. 250,326, dated November 29, 1881. Application filed March 28, 1881. (No specimens.) Patented in England August 20, 1880.

To all whom it may concern Be it known that I, PETER DE VILLIERs, of

- St. Leonards-on-Sea, England, doctor of medicine, have invented an improved inoxidizable ditions, as hereinafter specified.

I have discovered that when tin is suitably combined with lead and silver in the proportions herein specified an alloy is produced which will not only strongly adhere to iron and steel, but will impregnate these metals when they have been properly prepared to receive the alloy. The proportions of the metals in my improved alloy may be somewhat varied, according to the purpose for which the alloy is to be used. I prefer, however, to use the proportions indicated in the following formulas, by weight:

First formula: tin,eighty (80) parts; lead, eighteen (18) parts; silver, two (2) parts; total, one hundred (100) parts.

Second formula:- tin, ninety (90) parts; lead, nine (9) parts; silver, one (1) part; total, one hundred (100) parts.

I prefer the second formula when the alloy is to be applied to iron or steel.

In practicing my invention I proceed as follows that 18 to say, the tin is first melted, and when a brilliantwhiteness of the surface of this metal indicates its thorough fusion the lead is added in a granular state, and the mixture is slowly stirred, preferably with a rod of very dry fir-wood. The silver, separately melted, is added to and mixed in like manner with the compound. At this moment the fire under the melting-pot or crucible containing the alloy must be quickly increased till the surface of the metal has a slight yellow tinge. It is then rapidly stirred and run into molds to form ingots.

When I have the choice between iron or pose I proceed as follows: The blade is immersed in a bath of a solution of muriatic or sulphuric acid in the following proportions, by Weight, viz: one hundred (100) parts of distilled water or filtered rain-water, and from one (1) to ten (10) parts, by Weight, of muriatic acid or of sulphuric acid. The blade must remain in this bath for a longer or shorter time, according to its thickness, in order that it may be slowly and thoroughly penetrated by the same, this result being indicated by the appearance of spots on the surface of the metal. Instead of the acid solution, I may use aquafortis, the time of immersion in this case being very short. When the blade is withdrawn from the bath it mustimmediately be plunged in pure water, to be quickly and completely washed, and then it is wiped and dried as rapidly as possible with a piece of old linen, soft leather,

or a very dry sponge. It is then subjected for about five minutes to a dry heat in a furnace or oven heated to or centigrade. It is then withdrawn and again wiped.

'Iheprecedingoperationshavefortheirobject the preparation of the iron or steel for impregnation with the alloy, the result being that the said iron or steel is perforated with a multitude of holes almost infinitesimally small. In iron, unless this metal is of excellent quality, the size of these holes is extremely variable, and sometimes there are defective parts which make the subsequent operations very difficult. In steel the difference of diameter of these holes is almost imperceptible, so that the subsequent operations are performed without difficulty. This is the chief reason of my preference for steel.

The knife-blade or other article, after its preparation as above described, is immersed in a metallic bath composed of the alloy made according to one or the other of the formulas hereinabove given.

The ingots are melted over a moderate fire in a crucible or pot formed of plumbago or refractory clay, and not in an iron vessel, as particles of the iron would mix with the alloy and render the same liable to oxidize in the open pregnated knife-blade or other article.

The iron or steel, previous to immersion in the metallic bath or alloy, must be heated to a temperature of 50 or 60 centigrade. The bath must be perfectly liquid and stirred. with a dry rod of fir-wood or poplar, and the surface of the molten alloy must present a fine silverwhite color, which is obtained by slow fusion and by stirring only when the whole of the mass is liquefied. If these precautions are observed, the impregnation ot' the iron or steel will proceed rapidly, and the alloy will enter the artificially-produced holes and the pores of the metal, which are slightly dilated by the previous heating of the said metal. For a knifeblade or similarly thin object an immersion in the alloy of a very short timesay a few seconds-will suffice. Aperiod of from two to five minutes will he required for pieces or articles of greater thickness-such as horses bits, stable-chains, and the like. When withdrawn from the metallic bath the blade or other article of iron or steel is at once immersed in cold water, oris otherwise properly treated to harden or temper it, or to restore its temper, as required. It left in the cold water for too long a time, the metal sometimes becomes brittle; but carefulness on the part of the operator will prevent any difficulty of this kind. The blade or other article, having been wiped and dried without the application of heat, is polished in any suitable manner. It will then have the whiteness and luster of silver, and will have a ring or sound analogous to that of the latter metal, and may be considered inoxidizable under ordinary atmospheric conditions.

In my improved alloy the diiferent metals thereof impart to the same specific properties or qualities without which it would be unfit for the purpose of my invention-that is to say, the tin imparts pliability to the said alloy, the silver renders it hard, lustrous, and iuoxidizable, and the lead increases its fluidity and power of penetration into the interstices and pores of the iron, steel,or other metal, and I thus produce an alloy in which a very small proportion of silver imparts to the alloy and to steel or other metal to which the same is applied the hardness, whiteness, luster, and inoxidability of pure silver. Having thus fully described my said invention and the manner of performing the same, I wish it understood that I do not claim the mere application of silver or other like metal as a covering or coating for articles made of iron or steel, as I am aware that knives and other articles have been coated with silver by the aid of an intermediate layer of brass or copper applied to the surface of the steel to form a surface to which the silver can adhere, as this latter metal cannot with advantage be applied directly or without some intermediate metal to the surface of steel or iron. Moreover, I am aware that silver, tin, and lead have been alloyed together in the course of scientific investigation with regard to the properties of alloys, and that alloys of these metals have been used by coiners of counterfeit money; but all of such alloys contain a very large proportion ofsilver. (about forty to sixty per cent.,) and are practically useless for ordinary manufacturing purposes, and especially unfit and inapplicable for the purpose of my invention, and it was only by a long-continued course of experiments that I have discovered the precise manner or progressive order of combining these metals to make the above-described alloy, in which the silver unites with the tin and lead in the proportions and with the results above specified, and I particularly wish it understood that I do not claim any alloyin which the three metals are not combined in such proportions as will impart to the'alloy the peculiar properties necessary for the purpose of my invention, as above specified but I claim as my invention The alloy consisting of tin, lead, and silver, combined in or about in the proportions and in the manner above described, for the purposes specified.

PETER DE VILLIERS.

Witnesses:

WM. R0121. LAKE, BERNHARD DUKES. 

